gstreamermm: Gst::EventSegment Class Reference

gstreamermm 1.10.0

Public Member Functions | Static Public Member Functions | List of all members
Gst::EventSegment Class Reference

A segment event. More...

`#include <gstreamermm/event.h>`

Inheritance diagram for Gst::EventSegment:
[legend]

## Public Member Functions
Gst::Segment | copy_segment () const
| Parses a segment event and copies the GstSegment. More...
Public Member Functions inherited from Gst::Event
void | reference () const
| Increment the reference count for this object. More...
void | unreference () const
| Decrement the reference count for this object. More...
GstEvent* | gobj ()
| Provides access to the underlying C instance. More...
const GstEvent* | gobj () const
| Provides access to the underlying C instance. More...
GstEvent* | gobj_copy () const
| Provides access to the underlying C instance. The caller is responsible for unrefing it. Use when directly setting fields in structs. More...
| Event ()=delete
| Event (const Event&)=delete
Event& | operator= (const Event&)=delete
Gst::Structure | get_structure () const
| Access the structure of the event. More...
bool | has_name (const Glib::ustring& name) const
| Checks if event has the given name. More...
guint32 | get_seqnum () const
| Retrieve the sequence number of a event. More...
void | set_seqnum (guint32 seqnum)
| Set the sequence number of a event. More...
gint64 | get_running_time_offset () const
| Retrieve the accumulated running time offset of the event. More...
void | set_running_time_offset (gint64 offset)
| Set the running time offset of a event. More...
Glib::RefPtr< Gst::Event > | copy () const
| Copy the event using the event specific copy function. More...
Glib::RefPtr< Gst::Event > | create_writable ()
| Makes a writable event from the given event. More...
bool | is_downstream () const
| Check if an event can travel downstream. More...
bool | is_serialized () const
| Check if an event is serialized with the data stream. More...
bool | is_upstream () const
| Check if an event can travel upstream. More...
EventType | get_event_type () const
| Get the Gst::EventType of the event. More...
Gst::ClockTime | get_timestamp () const
| Get the Gst::ClockTime timestamp of the event. More...
Public Member Functions inherited from Gst::MiniObject
void | reference () const
| Increment the reference count for this object. More...
void | unreference () const
| Decrement the reference count for this object. More...
GstMiniObject* | gobj ()
| Provides access to the underlying C instance. More...
const GstMiniObject* | gobj () const
| Provides access to the underlying C instance. More...
GstMiniObject* | gobj_copy () const
| Provides access to the underlying C instance. The caller is responsible for unrefing it. Use when directly setting fields in structs. More...
| MiniObject ()=delete
| MiniObject (const MiniObject&)=delete
MiniObject& | operator= (const MiniObject&)=delete
| ~MiniObject ()
guint | get_flags () const
void | set_flags (const guint& value)
gint | get_refcount () const
gint | get_lockstate () const
bool | lock (LockFlags flags)
| Lock the mini-object with the specified access mode in flags. More...
void | unlock (LockFlags flags)
| Unlock the mini-object with the specified access mode in flags. More...
bool | is_writable () const
| If mini_object has the LOCKABLE flag set, check if the current EXCLUSIVE lock on object is the only one, this means that changes to the object will not be visible to any other object. More...
Glib::RefPtr< MiniObject > | create_writable ()
| Checks if a mini-object is writable. More...
void | set_qdata (GQuark quark, QuarkData* data)
| This sets an opaque, named pointer on a miniobject. More...
QuarkData* | get_qdata (GQuark quark) const
| This function gets back user data pointers stored via set_qdata(). More...
QuarkData* | steal_qdata (GQuark quark)
| This function gets back user data pointers stored via set_qdata() and removes the data from object without invoking its destroy() function (if any was set). More...
void | add_finalize_notifier (const SlotFinalizer& slot)
| Adds notifier when mini object is finalized. More...
void | remove_finalize_notifier ()
| Remove finalize notifier. More...

## Static Public Member Functions
static Glib::RefPtr< Gst::EventSegment > | create (const Gst::Segment& segment)
| Create a new SEGMENT event for segment. More...

## Additional Inherited Members
Public Types inherited from Gst::MiniObject
typedef sigc::slot< void > | SlotFinalizer
Protected Member Functions inherited from Gst::Event
void | operator delete (void*, std::size_t)
Protected Member Functions inherited from Gst::MiniObject
void | operator delete (void*, std::size_t)
Related Functions inherited from Gst::Event
Glib::RefPtr< Gst::Event > | wrap (GstEvent* object, bool take_copy=false)
| A Glib::wrap() method for this object. More...
Related Functions inherited from Gst::MiniObject
Glib::RefPtr< Gst::MiniObject > | wrap (GstMiniObject* object, bool take_copy=false)
| A Glib::wrap() method for this object. More...

## Detailed Description

A segment event.

See create() for more details.

## Member Function Documentation

## ◆ copy_segment()

Gst::Segment Gst::EventSegment::copy_segment | ( |  | ) | const

Parses a segment event and copies the GstSegment.

Returns
  A copy of a Gst::Segment.

## ◆ create()

static Glib::RefPtr<Gst::EventSegment> Gst::EventSegment::create | ( | const Gst::Segment& | segment | ) |
| static

Create a new SEGMENT event for segment.

The segment event can only travel downstream synchronized with the buffer flow and contains timing information and playback properties for the buffers that will follow.

The segment event marks the range of buffers to be processed. All data not within the segment range is not to be processed. This can be used intelligently by plugins to apply more efficient methods of skipping unneeded data. The valid range is expressed with the start and stop values.

The time value of the segment is used in conjunction with the start value to convert the buffer timestamps into the stream time. This is usually done in sinks to report the current stream_time. time represents the stream_time of a buffer carrying a timestamp of start. time cannot be -1.

start cannot be -1, stop can be -1. If there is a valid stop given, it must be greater or equal the start, including when the indicated playback rate is < 0.

The applied_rate value provides information about any rate adjustment that has already been made to the timestamps and content on the buffers of the stream. ( rate * applied_rate) should always equal the rate that has been requested for playback. For example, if an element has an input segment with intended playback rate of 2.0 and applied_rate of 1.0, it can adjust incoming timestamps and buffer content by half and output a segment event with rate of 1.0 and applied_rate of 2.0

After a segment event, the buffer stream time is calculated with:

time + (TIMESTAMP(buf) - start) * ABS (rate * applied_rate)

Parameters

  segment | A Gst::Segment.

Returns
  The new SEGMENT event.